BackwardπNCharge-Exchange Scattering and Pole Extrapolations of Baryon Regge-Exchange Amplitudes

Abstract

High-energy ${\pi }^{\pm }p$ backward elastic-scattering data are analyzed in terms of $N_{\alpha }$ and ${\Delta }_{\delta }$ Regge exchanges. Using the signs of the Regge residues found from extrapolations to the particle poles (which agree with the signs obtained from interference with direct-channel resonances), we predict the ${\pi }^{-}p\to {\pi }^{0}n$ cross section near 180°.